


Holding the Leash

by Vexatious



Category: Undertale (Video Game)
Genre: Aftercare, Alternate Universe - Underfell, Dominant Papyrus, Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Vagina (Undertale), Fellcest - Freeform, Fontcest, Light Bondage, M/M, Marking, Rough Oral Sex, Rough Sex, Underfell Papyrus, Underfell Sans, Watersports, submissive sans
Language: English
Status: Completed
Published: 2017-11-25
Updated: 2017-11-25
Packaged: 2019-02-06 13:55:47
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,716
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12818973
Author URL: https://archiveofourown.org/users/Vexatious/pseuds/Vexatious
Summary: Papyrus may think he's the Boss, but someone else is holding the leash...





	Holding the Leash

**Author's Note:**

> Don't forget to check out my [Tumblr](http://vex-bittys.tumblr.com)!

Papyrus never entered the house quietly, but today he slammed through the door like a herd of clumsy  _skelephants_. Sans couldn’t help the grin that slid across his features. An angry Papyrus was exactly what he needed to satisfy the itch of lust that afflicted him almost constantly. The Fell collectively frowned on vulnerability, but living with his brother gave Sans a unique opportunity.

He could never ask his brother for sex outright, oh no; Papyrus embodied the emotionless kill or be killed attitude of the Fell perfectly. He’d sneer at Sans’ weakness and mock his pitiful need for closeness, so Sans had to get creative. Papyrus was a predictable and easy mark. On a day like today, his brother would be putty in his hands. All he had to do was play his cards right.

Sans leaned back and sank into the couch, deliberately making his posture as slouched and lazy as possible. Papyrus stomped halfway up the stairs before spotting him. His already scowling face pinched further, and his eye sockets narrowed dangerously as he prowled into the living room like a lanky predator to stand in front of the shorter skeleton. “Sans,” he growled, that one single syllable dragging shivers of pleasure down his spine.

“After the day I had, working my ass off in the Royal Guard, I come home to find you lazing the day away on the sofa?” His grating voice held hints of angry frustration already. Perfect.

“Does it really surprise you that I’m  _sofa king_  lazy?” Sans gave Papyrus his best shit-eating grin.

“It surprises me that I haven’t knocked the rest of your teeth out,” snapped Papyrus, grabbing his arm, yanking him bodily from the couch, and tossing him carelessly  to the carpet, “and pick up that fucking sock!” Papyrus whirled and stomped up the stairs to change out of his heavy battle body; Sans made himself comfortable on the floor, biding his time.

Papyrus came back downstairs, padding quietly in socks and slacks, preparing to pull on a tank top when he spotted his brother still laying in the same position on the floor! “I told you to  _pick up your fucking sock_ , Sans!” he shouted.

“I did… see?” Sans turned the sock blue with magic and lifted it into the air with a wave of his hand before letting it fall back to the floor. Papyrus ground his sharpened teeth together in irritation. “Sheesh, Paps, you seem tense,” continued Sans, feigning innocence, “you want me to read Fluffy Bunny to you like I did when you were a babybones?”

Papyrus’ eye socket twitched as the fragile control over his temper snapped; his hands clenched into fists tearing the fabric of his tank top in half. In situations like these, he itched to knock some sense into his older brother’s thick skull, but Sans’ 1 HP limited his options. There was more than one way to express violence though…. 

Papyrus dragged Sans up off the floor by one arm, shoving him stomach down onto the couch before snatching his other arm and pulling both limbs into a painfully awkward position behind the smaller skeleton’s back. Sans yelped, but his brother ignored him, tying his elbows and wrists together with the remnants of his torn shirt. Next he withdrew a leather leash from his pocket and attached it to the loop in Sans’ collar.

He yanked on the leash, pulling Sans upright by his neck. “What did you call me?” The tall skeleton’s voice was low and dangerous, yet the glowing bulge in the front of his pants gave away his eager anticipation for his brother’s punishment.

“P-Papy,” repeated Sans, sweating and drooling slightly at the red glow that held the promise of intense pleasure. Papyrus yanked the leash again sharply, choking him.

“Address me correctly,” ordered Papyrus, tugging his brother’s shorts down with his free hand and giving his sensitive, glowing pubis a sharp flick.

“Yes, Boss,” Sans whined, his breath accelerating at the rough treatment. He couldn’t hold back the needy little moan that escaped him when Papyrus let his own pants fall to the floor, freeing his glorious spiked cock. His tongue lolled from his gaping mouth as he salivated, wanting desperately to taste the precum beading and then dripping in viscous strings from Papyrus’ tip.

“What are you waiting for, idiot? It’s not going to suck itself!” Papyrus hissed in irritation. How dense could the smaller skeleton possibly  _be_? Was he  _trying_  to annoy the Great and Terrible Papyrus?

“I’d give you a hand, but I’m a little  _tied up_  at the moment!” Sans planned his latest line to push his already seething brother over the edge, and it worked. Oh boy, did it work.

Papyrus’ sockets went black then flared with red magic. He grabbed Sans by the skull and dug his sharpened phalanges into the bone with a grating scraping sound. He bucked his hips forward, pulling Sans towards him and burying his length to the base in his brother’s throat. Skeletons have no gag reflex, Sans reminded himself as the thick member invaded the delicate magic of his throat; he couldn’t choke either. Holding Sans’ head in place with a crushing grip, Papyrus fucked the other skeleton’s throat brutally, relishing the feeling of his cock penetrating so deeply. Sans lapped the spiky underside of his member and attempted to suck it, but Papyrus preferred violating his brother’s mouth to a conventional blowjob.

As Papyrus felt his orgasm building, he faced the tough decision of making the smaller monster swallow his cum or spraying his seed on his face. He slammed his cock down Sans’ throat and came hard, shuddering with the release as thick strands of hot cum filled his brother’s throat until it spilled from his mouth and ran down his chin. Sans swallowed as much as he could, but Papyrus’ load was too much. He toppled onto the floor, gasping.

“You can’t possibly think you’re done, Sans. Make something for me to fuck.” Papyrus leered at his slut of a brother, who had obediently formed a slick, eager pussy and swollen clit for the tall skeleton’s pleasure. He pressed his thumb to the nub and ran two fingers up and down Sans’ slit. Moans poured freely from Sans’ mouth under his brother’s expert touches, but Papyrus wasn’t interested in any pleasure except his own. He pinched and twisted Sans’ clit as he fingered his pussy hard and fast, curling his fingers to stroke the sensitive walls.

“Wait… Boss… hah-ah… too much… please…” Sans whimpered and moaned to the background noise of lewd squelching. He could feel his juices coating his femurs and running down Papyrus’ hand.

“You seem to have finally found some manners, Sans,” Papyrus laughed darkly. “Please what?”

“Please, Boss… more… harder… m-make me cum!” Papyrus answered him with another laugh.

“What makes you think you deserve to cum?” Papyrus quickly and easily lifted Sans into his lap, spreading his pussy with two fingers as he shoved Sans down forcefully onto his cock. Sans gasped as the thick length filled him, stretching his pussy deliciously and leaving him a moaning, begging mess. Holding him by the femurs, Papyrus lifted Sans and slammed him down onto his sensitive, throbbing member, breaking a sweat himself. Sans mewled for harder, faster fucking, and Papyrus obliged, pounding into him mercilessly until he came, his tight walls vibrating and clenching around his cock.

Papyrus didn’t pause or slow down; Sans eyelights turned to hearts shortly before rolling back in his sockets as he panted and drooled, tongue lolling. “Make me your fucktoy, Boss!” Sans’ mind was clouded with a mixture of lust and exhaustion as another orgasm shook him. Papyrus shoved his face into the carpet and began fucking him from behind, rougher and faster, completely silent as he focused on destroying his brother’s pussy.

The new angle allowed him deeper access, and his cock pushed into Sans’ cervix before finally forcing its way through. He fucked his brother’s uterus, finally feeling the pulse of a second orgasm building as Sans writhed and screamed beneath him, from pleasure or pain, Papyrus didn’t know or care. He dug his clawed finger bones into Sans hips and came in his womb. He felt the swirling warmth around his cock as his cum filled his brother, and he rode out his orgasm inside of the other monster.

Sans laid on the floor, a trembling mess, breathing hard, cum dribbling from his bruised hole, but Papyrus still had one more act to add to the punishment, one more thing he needed to do so that Sans would remember his place. The small skeleton looked at his brother tiredly, realizing too late why Papyrus had summoned an ectobody as a stream of hot piss hit his cheek.

The tall skeleton pissed on his brother’s prone figure, then helped him into a sitting position to untie him and remove the leash. “Don’t wash it off,” he warned Sans. “I want you to remember who is the master of this house.” Sans could feel the urine soaking into him, and he knew the scent would last; Papyrus had marked him.

Sans was too worn out to move, so Papyrus scooped him up and carried him to his bedroom. By the time Papyrus laid his brother in his bed, he had already fallen asleep. Papyrus observed him for a few moments. He protected Sans, worked hard to keep them safe and fed. He had to maintain his reputation; he couldn’t afford to be weak. If that meant demanding complete obedience from Sans, so be it. Still, he couldn’t help feeling a twinge of guilt for being so rough on his brother, a guilt he had to squash for their own good. He pressed his mouth to his sleeping brother’s skull and left the room.

Sans waited until he was certain Papyrus wouldn’t come back before opening his sockets and allowing himself a sly smile. Love wasn’t easy to come by in their kill or be killed world, but it existed if you looked for it and knew how to play your cards right. Sans chuckled quietly, a whisper of a laugh so as not to alert his brother. He might wear the collar, but he also held the leash.


End file.
